<template>

  <div class="city_body">

    <div class="city_list">
      <div class="city_hot">
        <h2>热门城市</h2>
        <ul class="clearfix">
          <li v-for="(item,index) in hotList" :key="item[index]">{{ item }}</li>
        </ul>
      </div>
      <!--    <button @click="test">test</button>-->
      <div class="city_sort" ref="city_sort">
        <div v-for="item in cityList.cityList" :key="item.index">
          <h2>{{ item.index }}</h2>
          <ul>
            <li v-for="itemList in item.list" :key="itemList.id">{{ itemList.nm }}</li>
          </ul>
        </div>
      </div>
    </div>

      <div class="city_index">
        <ul>
          <li v-for="(item,index) in cityList.cityList" :key="item.index" @click="handToIndex(index)">
            {{ item.index }}
          </li>
        </ul>
      </div>

  </div>

</template>

<script>
export default {
  name: 'cityIndex',
  data() {
    return {
      cityList: [],
      hotList: []
    }
  },
  mounted() {
    this.axios.get('/cities.json').then((re) => {
      console.log(re)
      const cities = re.data.cts;
      const cityList = this.formatCityList(cities);
      const hotList = re.data.hot
      this.cityList = cityList;
      this.hotList = hotList;
      // console.log(this.hotList);
    })
  },
  methods: {
    // test(){
    //   console.log(this.cityList)
    // },
    formatCityList(cities) {
      const cityList = [];
      // var hotList = [];


      for (let i = 0; i < cities.length; i++) {
        const firstLetter = cities[i].py.substring(0, 1).toUpperCase();
        if (toCom(firstLetter)) {
          cityList.push({index: firstLetter, list: [{nm: cities[i].nm, id: cities[i].id}]})
        } else {
          for (let j = 0; j < cityList.length; j++) {
            if (cityList[j].index === firstLetter) {
              cityList[j].list.push({nm: cities[i].nm, id: cities[i].id})
            }
          }
        }
      }

      cityList.sort((n1, n2) => {
        if (n1.index > n2.index) {
          return 1;
        } else if (n1.index < n2.index) {
          return -1;
        } else {
          return 0;
        }
      })

      function toCom(firstLetter) {
        for (let i = 0; i < cityList.length; i++) {
          if (cityList[i].index === firstLetter) {
            return false;
          }
        }
        return true;
      }

      console.log(cityList)
      return {
        cityList
      }
    },
    handToIndex(index) {
      const h2 = this.$refs.city_sort.getElementsByTagName("h2");
      this.$refs.city_sort.parentNode.scrollTop = h2[index].offsetTop;
    }
  }
}
</script>

<style scoped>
.city_body {
  margin-top: 45px;
  display: flex;
  width: 100%;
  position: absolute;
  top: 0;
  bottom: 0;
}

.city_body .city_list {
  flex: 1;
  overflow: auto;
  background: #FFF5F0;
}

.city_body .city_list::-webkit-scrollbar {
  background-color: transparent;
  width: 0;
}

.city_body .city_hot {
  margin-top: 20px;
}

.city_body .city_hot h2 {
  padding-left: 15px;
  line-height: 30px;
  font-size: 14px;
  background: #F0F0F0;
  font-weight: normal;
}

.city_body .city_hot ul li {
  float: left;
  background: #fff;
  width: 29%;
  height: 33px;
  margin-top: 15px;
  margin-left: 3%;
  padding: 0 4px;
  border: 1px solid #e6e6e6;
  border-radius: 3px;
  line-height: 33px;
  text-align: center;
  box-sizing: border-box;
}

.city_body .city_sort div {
  margin-top: 20px;
}

.city_body .city_sort h2 {
  padding-left: 15px;
  line-height: 30px;
  font-size: 14px;
  background: #F0F0F0;
  font-weight: normal;
}

.city_body .city_sort ul {
  padding-left: 10px;
  margin-top: 10px;
}

.city_body .city_sort ul li {
  line-height: 30px;
  line-height: 30px;
}

.city_body .city_index {
  width: 20px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  text-align: center;
  border-left: 1px #e6e6e6 solid;
}
</style>
